Composition for shoe manufacture and process of making shoes



DeC- 28, 1937. P. J. wl-:NTwoRTH 2,103,884

COMPOSITION FOR SHOE MANUFACTURE AND PROCESS OF MAKING SHOES Filed July A31, 1954 INVENTOR. Uf/)IPL JM/vrWo/Prh'.

BY v

MU ME ATTORNEY Patented Dec. 28, 1937 PATENT oFFicE COMPOSITION FOR SHOE MANUFACTURE AND PROCESS OF MAKING SHOES Pearl J. Wentworth, Fort Thomas, Ky. Application `luly 31, 1934, Serial No. 737,811

16 Claims..

My invention Yrelates broadly to a resilient insert or layer between the insole of a shoe and the outer sole thereof, to a particular composition for the purpose and to a method of manufacturing s shoes. It has been the practice hitherto asis well known, to manufacture shoes by aixing an insole to a last and by attaching an upper to the insole thereon. Then it has been the practice to position, in some Atypes of shoes, a resilient material over the insole or over a single portion or interspaced portions thereof, afterward attaching the outer sole so that the resilient material forms a cushion between thel insole and the oute-r sole. For the most part the practice has been to use an 1.5i insertof preformed material, although some attempts have been'made to spread a resilient material such as cork particles in a binder over the insole. Neither of these procedures have hitherto been entirely without disadvantage. Many sub- 26 stances so used do not 'retain their resiliency, some of them disintegrate and many of them creep.

" Itis an object of my invention to provide a newV substance for this use. It is an object of my ino vention to provide such substance initially in plastic form so that it may be formed into required inserts in a variety of ways. It is my object to provide a composition which will easily spread, is sufficiently elastic, permanently resilient, and not subject to creeping. It is van object of my invention to provide a substance which will be quite inexpensive and lvery economical to use. VIt is' likewise an object of my invention to provide a novelY procedure in the manufacture of shoes. D These and other objects of rmy invention I attain in that certain composition and by that process of which I shall now describe certain exemplary embodiments.

In the drawing I have shown, to illustrate one 40 form* of my process, a last with an insole and anV upper thereomand some of my composition being troweled into place to form an insert, in Figure l. In Figure 2 I have shown a partial cross section of a completedv shoe. n

Essentially in the practice of my invention, I Vprovide a composition comprising rubber as the binder in combination with a resilient filler material and a. brous or spreading material of a particular kind. My composition is one in which a Working plasticity is-obtained by means of a sol- Vent. Since compositions of this character' are l apt, upon evaporation of the solvent,.to'contract, and since in one ,aspect of my process such contraction, upon drying, would be highly undesirable, I preferably incorporate into my composition a portion of a material which prevents contraction upon drying Without destroying resilience.

In the manufacture of my composition, I employ as a primary binder, a rubber solution or cut rubber. YThis may be of any well known type. I prefer to employ about a 9% solution of pure gum rubber in any of the commercial rubber solvents which are well known; but I am not limited thereto. For the ller material I may use any powdered or granular material, thoughpreferably of resilient character, such for example as ground cork, but I prefer to employ ground up tire carcass, or other rubber waste which may, without harm and possibly with some advantage, contain 1i some or all of the organic fiber with which the rubber was originally associated in the article.

Asthe spreading ingredient I use a mineral ber, preferably a rock or glass wool, usually obtained by spinning glass furnace slag or the like. After a mixing operation, thebers become relatively short and they give a satisfactory body, while providing a composition which can be troweled smoothly in a relatively thin layer.

In making up my composition, by way of ex- -5- ample but without limitation, I may take sixtyfoury ounces of the rubber solution, to which I add eight. ounces of rock wool and thirty-four ounces of ground tire carcass, and I mix these ingredients together in a suitable mixing machine, say of the 30 Werner-Pfleiderer type. The resulting composition is a plastic which may be placed in air tight cans or other containers until its use is required.

When used in the manufacture of shoes, this Y composition may be sheeted as by rolls 'or vther like, or a troweling operation, and may be dried and cut into inserts of the required size. y

It is preferable, for economy in manufacture however, to employ the composition asv such. in the manufacture of shoes.v I have found that the composition for this purpose is very much iml proved by theaddition of an ingredientwhich will prevent contraction upon drying without' de- Y stroying elasticity or resilience. Such an ingredient may be in one of the natural gums of' Wax-like or bituminous substances dissolved in a solvent. I have found it preferable to use a gum known as niger gum dissolved ina fast naptha until a thinliqui'd is'obtained. When manufacturing a composition in accordance with the formula given above, I prefer to add 18 ounces of the contraction preventing ingredient., Ordinarilyit will be found preferable to mix the contraction preventing ingredient with the rubber solution first, afterward adding and mixing in the rock wool and lci d ofV the solvent, an excellent adhesive bond, is

nally mixing in the powdered or granular Waste rubber material.

This composition does not contract upon drying and elimination of the solvent; consequently it may be troweled into'place upon an insole Without the necessity of halting the process of manufacture of the shoeV until the material is dried, and afterward lling up the cracks-left by the contraction thereof. I have shown in the drawing a last i, to which an insole 2 is attached, and I have'shovvn also the upper 3 in place. The edges of the upper lying over the edges of the insole leave a centrallyV depressed space as shown, into which my composition 4 may beV lThe composition may troweled as by a knife 5. be troweled all over the insole,` or over only a part thereof, or over interspaced toe and heel V-portions as may be desired. Applied before the solvent has evaporated, the compositionv makes a good bond With the insole and adjacent parts, and by reason of the fact that it does not contract upon drying, theV manufacture of the shoe may continue in an uninterrupted manner. TheV outer sole may be applied to the structure aforesaid, and when this is done prior to the drying formed with the outer 'sole as Well. VThe composition dries into a tough, tenacious',.fairly elastic and Very resilient mass, which is not subject to displacement or creeping.

VModiiications may be made Vin my'invention without departing from the spirit thereof, but What I claim as new and desire to secure by Letters Patent iszl. A shoe ller, comprising as Va principal ingredient, `ground-up Vtire carcass, a binderya solvent therefor, Vand a Vcontraction preventing` material selected from a group consisting of the natural gums of Wax-like or bituminous substances dissolved in a solvent.

2. A shoe ller, comprising as a principal ingredient, prevulcanizedV rubber granules existing as such, a binder, Va solvent therefor, and a contraction preventing material selected from a group consisting of the natural gums of Wax-V like or bituminousjsubstances dissolved in a solvent.

3. A shoe ller, comprising'as'a principal in- Y* gredient,` ground-up tire carcass, a a solventV therefor, and Niger gum. .Y

4. A shoe filler, comprising as a principal ingredient, ground-up tire carcass, and an articial binder Vand Y `mineral fiber, a binder and a solvent therefor,

. and a contraction preventing materialselected 'from a group consisting of the natural gums of Y Wax-like or bituminous substances dissolved in a solvent.

' rubber granules existing as such, a binder and a'solventtherefor, the quantity of the binder being so proportioned to the Whole, that when the solvent is driven off the mass remains porous.

7. A shoe filler comprising rubber cement and articial mineral fibre and ground-up tire carcass. A

Y8. A shoe filler comprising rubber cement, mineral Wool and ground-up tire carcass.

9. A shoe filler comprising rubber cement, rock Wooland ground-up tire carcass.

l0. A shoe filler comprising rubber cement as Y a continuous binden'ground-up tire carcass as Ya ller material and a contraction preventing material selected from a group consisting of the natural Vgums of wax-like or bituminous substances dissolved in a solvent. Y

1l. A shoe filler comprising rubber cement, rock Y Wool, ground-up tire carcass and a contraction preventing material selected from a group consisting of the Vnatural gums of Wax-like or bituminous Vsubstances Y dissolved in a solvent.

, 12. A shoe ller vdescribed inclaim 8 containing an organic gum .as a contraction preventing agent. Y, v Y 13JA shoe ller described 'inV claim 9 containing an organic gumY as a contraction preventing material; Y

14. A shoe ller comprising rubber cement as a binder, ground-up tire carcass as a ller ,mate-z rial Yand Niger gum as a contraction preventing material. Y

15. A shoe Viller for the purpose described comprising a rubber cement binder, a granular resilient filler. and an artificial mineral fibre-of` smooth character, to give body to' the mass and to facilitate smooth spreading as by troweling and' quick drying; Y.

16.Y A shoe iiller for the purposeV described comprising'a' rubber cement binder, aV granular re- *silient ller and an articial mineral fibre Vof smooth character to give body to' the mass and Vto facilitate smooth Yspreading as byftroweling and quick drying, saidY resilient filler comprising ground Vtire carcass. A

PEARL J. WENIWORTH. 

